The following issues can cause problems when reading printed barcodes:

1. Ink jet printers – Ink jet printers cannot usually print barcodes accurately when X (the X Dimension) is at .03CM (12 MILS) or less because the splattering ink distorts the barcode. For ink jet printers, increase X to .06 (24 MILS) to compensate for the splatter during printing and to get accurate barcodes. For barcode font users, this means printing at 20 points or more. Satisfactory output can sometimes be achieved by ink jet printers with the proper paper. However, experience has taught us that laser printers produce more consistent, accurate and dependable output. If there is a choice in printers, choose the laser.
2. Contrast and color problems – Check for proper contrast and proper barcode printing material. Normally, the barcode should be black and the background white. In most cases, using other colors will cause poor scanning conditions. Also, make sure the material is not too glossy or the scanner light will reflect and cause the barcode to improperly scan.
3. Low resolution and thermal printers – Problems may occur when printing barcodes on printers of 300 DPI or less. For more information, please refer to low resolution thermal printer and print quality requirements.
4. Web barcodes – if printing barcodes from a browser or web application, refer to the Web Browser Barcode Resolution FAQ.